On March 15, the New York City Department of Buildings released a statement on the crane collapse in Manhattan. Buildings inspectors, forensic engineers, and high-rise and crane experts responded to emergency calls regarding a crane collapse at 303 East 51st Street in Manhattan, a proposed 43-story new residential building under construction.

A tower crane installed at the construction site fell southward onto a property across the street at 300 East 51st Street, a 19-story residential building. The fall caused a portion of the tower crane’s mast, approximately 75 feet in length, to break and fall onto 305 East 50th Street, a four-story residential building with a restaurant/bar on the street level.

A preliminary investigation indicates the accident occurred while workers were adding tower sections to extend the crane upwards, an operation known as "jumping" the crane. While crews were jumping the crane to the 18th floor, a heavy-duty steel collar, which wrapped around the mast of the crane and was used to tie the crane to the side of the building, fell as workers attempted to install it. When the steel collar fell, it damaged a lower steel collar installed at the 9th floor. The collar installed at the 9th floor served as a major anchor, securing the tower crane to the building under construction. With the elimination of the support provided by the steel collar at the 9th floor, the counter-weights at the top of the crane’s tower caused the entire structure to fall southward.

The investigation into the exact cause of the accident continues. Forensic engineers and inspectors from the Buildings Department remain on scene to provide structural expertise once remedial work begins to remove the broken crane and debris from the accident.

Buildings forensic engineers have confirmed at least seven buildings sustained damage during the accident. As the remaining parts of the collapsed crane are removed from the site at 305 East 50th Street, the focus will turn to working with the respective owners to repair and secure buildings that sustained damage.

Owned by New York Crane and manufactured by the Favelle Favco Group, the tower crane has been inspected approximately five times over the course of its operation history at 305 East 51st Street. The permit for the crane was issued on Jan. 17, 2008 to JCI. The most recent inspection of the crane occurred on March 14, 2008. On that day, inspectors with the Buildings Department’s Cranes & Derricks Unit inspected the mast sections to be used to jump the crane during the March 15-16 weekend. No violations were issued as a result of that inspection.

Prior to the March 14 inspection, the crane was documented as inspected on March 4, when Building Department inspectors scrutinized the crane in response to a complaint. However, on March 20, the New York City Department of Investigations arrested the crane inspector for falsifying inspection route sheets. The inspector allegedly falsely claimed he inspected the East 51st crane on March 4, 2008.

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